Could the cali carbs be the cause of my problems???

[ride92]

After reading that Radare just got 64mpg on his latest '92 project that really got me thinking about my bike and it's continuing trouble to crack the 40mpg marker. Now the bike is a California bike and has the charcoal canister and the cali carbs and what not with the extra little ports that face the front of the bike when installed. Currently those ports have a tube that run from one to the next connected by a tee and that tee is capped off with a little rubber "hat?" thing held on by a zip tie. I've played with the pilot screws until all pipes are reading about 500degrees at the bend +/- 20 degrees. I have done a valve clearance check and got all the shims within spec, then re checked the exhaust temps. And I've built a home made manometer and synced the carbs using that. After all that I'm only averaging 38 mpg!!! Also, the bike has a really hard time going above the 100mph mark as well. It seems the top speed for the bike is about 92mph. I have stock gearing, at least I think I do, the rear is a 48 tooth and I haven't pulled the front cover to inspect the front in a bit but I assume is a 16 tooth. For the life of me I can't figure out why I'm getting such poor mpg's. It's barely better then my car. I should add that I run a bit of seafoam about every other tank and that I did a compression test on the engine and all cylinder where well within specs. My only thought is that I'm having some sort of issue with the CA carbs, maybe those extra ports are leaking air or something. Anyone got some suggestions for me on what to do?